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How to shorten a 60-62 torsion bar X-frame, as properly as you can, and still keep the X.

I have not found any tutorial on how to shorten these frame; most people either cut the X out completely, or swap to a 63+ frame. Another exciting bit of fun, is the frame rails taper under the cab, that is: they narrow at the front. While most people shorten the 63-72 frames under the cab, you cannot do that on the 60-62.

Some say that the 60-62 trucks have the best ride quality, and attribute it to the torsion bar front suspension. I would attribute the better ride quality to a significantly more rigid frame. Though I'm sure the torsion bars spreading the spring rate along the front third of the frame could be a contributing factor.

Undaunted, I have a Sawzall and a welder, and I'm not afraid to use them. Keep in mind, I am -just- a guy with a Sawzall and a welder, nothing more.

First of all, there are three kinds of cuts you can do on a frame:

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Sadly, there really isn't enough cut-able area to do the optimal Z cut - there is ONLY enough room to cut out ONLY the amount that needs to be gone. So, you're stuck with the vertical cut, or a marginally angled cut. Just do straight cuts - with the extra legs of the X in the frame, it should be plenty strong. My current daily is a '77 Squarebody with a vertical cuts and it's been working fine (yes, I have hauled and towed stuff for years with it).

Knowing where to cut is key:

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I welded eight legs to the frame with threaded feet so I could level the frame and then brace the snot out of it. I also removed the front four bed mounts, as the holes really weren't going to work easily (you will need to drill two new holes for the front bed mounts).

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Then I cut the sections out. I kept the sections to use them as fish plates.

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I used ratchet straps and the gentle persuader to pull the two halves together. I also used ratchet straps to pull everything to square, and lots of clamps to hold it all true. This is where the legs with adjustable feet come into play again - since floors are never perfect, I had to re-level the frame halves as they sat in their new location. It didn't need much correction, and the X is holding it in alignment very well. I got to +/- 1/32" diagonals for squareness.

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My frame appears to be a tick under 3/16" thick, which is still really too much for my Lincoln 140 MIG welder. It -could- be done, but there is something to be said about a welder big enough to do the job properly.

I borrowed the Thermal Arc 210 Fabricator from work, which was awesome.The forward legs of the X will have to be pie cut at the top and bottom to bend the leg sections back into alignment with each other. I tried to heat-shrink them with a torch, but it took forever to get nowhere. Just slice them and bend them.

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I have a cheap eBay plasma cutter that has been working grand. Makes cutting the fishplates easy. I did the frame cutting with a cutting disc on an angle grinder.

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The fish plates will need a bit of bending, because of the shapes of the frame where the cutting occurred. I used a hydraulic press to bend them. Clamp them in tight, and burn 'em in. I lifted the frame on edge just for easier position for welding, but do whatever you need to do to make it work.

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Some say you should only fish plate the vertical welds and leave the top and bottom flanges alone. Others say you should fish plate all your welds. I'm not a welder. On my '77 I did not fish plate the tops and bottoms of the rails, and it's been sketching me out ever since. On this frame, I did tops and bottoms. Again, with the extra bracing the X provides, it will probably be fine either way. I'm also not an engineer.

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You will need to trim the fish plates to avoid the e-brake slots.

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I prefer to grind down only the welds that would be visible; don't grind anything you don't have to.

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And done, once I add the front bed mounts (use existing front hole, drill new rear hole):

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